What should you know about right side flank pain in pregnancy?

As pregnancy progresses, posture, ligaments, muscles, and pressure from the growing uterus can produce discomfort in the side or back. Pain that changes with position or activity may fit a mechanical cause, but it should not be assumed without considering other symptoms. Pregnancy can also make urinary problems clinically important: kidney infection may present with flank pain, fever, chills, nausea, or urinary symptoms, while kidney stones can cause severe wave-like pain and nausea. A urinary tract infection may cause burning or urgency and needs pregnancy-appropriate treatment. Your maternity or primary-care team can assess both you and the pregnancy.

Rest from activities that provoke the pain, change position gradually, and use supportive pillows when lying or sitting. Gentle movement may help if it feels comfortable. Drink normally unless your maternity team has prescribed a fluid limit. Do not take an over-the-counter pain medicine, herbal product, or antibiotic without checking that it is suitable in pregnancy. Contact your maternity team or clinician about new, persistent, or recurring flank pain; they may check your urine and examine you.

Seek urgent maternity or medical care for severe or worsening pain, fever, chills, repeated vomiting, fainting, confusion, difficulty breathing, blood in the urine, or inability to pass urine. Contact your maternity team urgently for vaginal bleeding, fluid leakage, regular painful contractions, or reduced fetal movement when you would normally feel movement. Do not wait for a routine appointment if you feel significantly unwell.

Could this be muscular, or do I need a urine test? Which pain relief is suitable at my stage of pregnancy? Should I be monitored for infection or contractions? Which changes should send me directly to maternity assessment?